Dyestuffs of the anthraquinone series



Patented Feb. 2, 1943 DYESTUFFS OF THE ANTHRAQUINONE SERIES Alexander J. Wuertz and Myron S. Whelen, Wilmington, Del., assignors to E. I. du Pont de Nemours & Company; Wilmington, Del., a corporation of Delaware No Drawing. Application March 26, 1941, Serial No. 385,304

1 Claim.

This invention relates to the production of new dyestuffs of the anthraquinone series and more particularly to the preparation of acid wool dyestuffs of the dianthraquinonylamine type.

properties.

type which are now available.

oxide content and at temperatures of from 90-100 C. Where boric acid or mercury salts are employed in the sulfonation, temperatures of from 120-150 may be used. The amount of boric acid employed should be in approximately The sulfonation is consid- The reaction mass is It dyes wool Very few of the anthraquinone compounds of 5 equal molecular proportions based on the dishhigher molecular weight such as those containing thraquinonylamine. two or more anthraquinone nuclei linked toered completed when test portions worked up in gether have been found commercially suited for the usual manner show complete solubility in use in the dyeing of wool, silk and related fibers, water. Usually from 2-3 hours are required to apparently because of their lack of afiinity when complete the sulfonation. The sulfonation prodconverted to the water soluble sulfonic acids. A not may be worked up by diluting the sulfonation few compounds, however, of higher molecular mass with water to an acid concentration of weight have been found to show sufiicient affrom 54-57% then filtering off the precipitated finity for W001 when converted to the water 501- dyestuff; or the sulfonation producti may be uble sulfonic acids to make them of possible drowned in Water and filtered off in which case use in this field. It has been found that in gena somewhat less pure product is obtained. The oral these higher molecular weight compounds product is obtained in the form of a dark powder show better fastness properties when applied to which when dry is readily soluble in water. It wool and silk than many of the lower molecular dyes wool from an acid bath in clear strong bluweight compounds of the anthraquinone acid ish gray shades and exhibits good fastness parwool series such as the arylaminoanthraquinone ticularly to light, fulling and washing. On sulfonic acids and there is a continuous search chroming this dyestuff shows comparatively litfor desirable colors in the anthraquinone field tle change in color being converted to a somewhich can be used for the dyeing of wool and what greener shade of gray, making it particusilk and which will exhibit improved fastness l'arly suitable for use in mixtures with other colors which require chroming. In this specifi- It is an object of this invention to prepare cation and claim the expression bluish gray wool dyestuffs of the anthraquinone series which is used in contradistinction to reddish gray for dye in gray shades a d Wh ch exhib t improved this color dyes in gray shades which do not confastness properties over the known dyestuifs of tain the red component which characterizes the similar shade of the arylaminoanthraquinone so-called reddish grays.

The following examples are given to illus- We have found that a very desirable bluish trate the invention. The parts used are by gray dyestuff can be produced in the anthraweight. quinone series which exhibits good fastness prop- Example 1 erties by condensing l-benzoylaminol-chloroanthraquinone with 1-amino-4-hydroxy-anthra- Fifteen (15) P rts Of y '0 Y- quinone, then hydrolyzing off the benzoyl grou 1:1'-dianthraquinonylamine are introduced unand sulfonating the product giving what is gen- 0 def good agitation into one hundred and y erally considered to be the 4-amino-4-hydroxy- (150) P ts O fuming sulfuric a o 8% free 1,1 -dianthraquinonylamine sulfonic acid. This S03 content, to which nine (9) parts of boric compound may of course be prepared over oth r acid and one-tenth (0.1) part of mercuric oxide routes such as by the condensation of l-benzoylhave been added- The reaction mixture is heataminol-aminoanthraquinone with 1-chloro-4- e W e stirring to until a test 1 hydroxy-anthraquinone with subsequent hytion readily dissolves in warm water, which usudrolysis of the benzoyl group and sulfonation, y takes about 2 hoursor it may be prepared by direct condensation of cooled, a d poured into 2000 Parts Of water, 1,4-diaminoanthraquinone with l-chloro-4-hytaining ten (10) parts of sodium sulfite, after droxy-anthraquinone in equal molecular prowhich three hundred (300) parts of sodium portions, with sulfonation of the resulting prodchloride are added and the whole is boiled. uct. The sulfonation of this compound, irre- After cooling the precipitated dyestufi is filtered spective of the method by which it is prepared, off, washed free from acid with 5% sodium chlomay advantageously be carried out in fuming ride solution and dried. A dark powder is thus obtained, easily soluble in water.

sulfuric acid of between 20-40% sulphur trifrom an acid bath clear bluish gray shades of excellent fastness properties.

Example 2 Seventy-five (75) parts of 4-amino-4'-hydroxy-1: 1-dianthraquinony1amine are dissolved, while agitating in nine hundred (900) parts of fuming sulfuric acid of 25% free SO; content to which have been added thirty (30) parts of boric acid and seven-tenths (0.7) part of mercuric oxide. One hundred (100) parts of fuming sulfuric acid of 65% free $03 content are then added and the whole is heated at 145 C., until a test portion shows complete solubility in warm water, which is usuallyv in about three hours. After cooling one thousand (1000) parts of water are added to the charge below 50 C., followed by twenty (20) parts of sodium bisulfite. After stirring for one-half hour the precipitated dyestufi is filtered off and the cake washed with seven hundred (700) parts of 50% sulfuric acid. The dyestufi is stirred in 5% brine solution, followed by filtration and washing of the cake with 5% brine solution until free from acid, after which it is dried. The product so obtained is a dark powder, easily soluble in water, which dyes wool from an acid bath in bluish gray shades of excellent fastness, especially towards washing, fulling and light.

Example 3 If in Example 2 the use of mercuric oxide is omitted, a product which dyes wool from an acid bath in bluish gray shades slightly greener than that obtained in Example 2 is obtained.

Example 4 If in Example 1, the use of mercuric oxide and boric acid is omitted during the sulfonation, the sulfonation takes place at 95-100" 0. The dyestuff so obtained is conveniently isolated by the method used in Example 2, and a. product slightly less pure than that obtained in Example 2 is secured, dyeing wool from an acidbath in bluish gray shades.

We claim:

The water soluble sulfonation derivative of 4 amino 4' hydroxy 1,1 dianthraquinonylamine which dies wool from the usual acid bath in clear strong bluish gray shades of good fastness properties.

ALEXANDER J. WUERTZ. MYRON S. WHELEN. 

